O'Rourke is challenging junior Republican Sen. Ted Cruz. Cruz, who voted early, had nothing on his agenda for Election Day other than to attend his watch party Tuesday night.

After voting, O'Rourke spoke with reporters outside of his polling location.

"Texas is not going to be, um, it's not going to be defined by our fears. We're gonna be governed by our ambitions. We're gonna be fiercely focused on the future and we're gonna do this together. We just do not care about the differences between us right now. We want all of us, Republicans and Democrats, Independents alike to come together and do something great for this country. That's what I've heard from the people of Texas over the last 22 months. That's what folks are voting for today and I think that's what it's going to represent.

The people of Texas have, in the most positive way, been defined by our connection to the rest of the world, our border with Mexico, we're a state of immigrants and asylum seekers and refugees. We know that the border's not a threat. We know that it's an opportunity. Whether you measure it in trade or jobs or economic growth, or you look at the composition of our families and our communities. Or the fact that El Paso, Texas today is one of, if not the safest cities in the United States of America, not in spite of, but because of the fact that we are a city of immigrants and that we're connected to Ciudad Juarez. I mean, this is our source of strength and success, and yes, I would argue also security. So, we in Texas know that and no one from outside is going to be able to stir enough paranoia or fear to change that."